enic: check dma_mapping_error

This patch checks for pci_dma_mapping_error() after dma mapping the data.
If the dma mapping fails we remove the previously queued frags and return
NETDEV_TX_OK.

Reported-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/cisco/enic/enic.h b/drivers/net/ethernet/cisco/enic/enic.h
index 25c4d88..b2ea35a 100644 (file)
--- a/drivers/net/ethernet/cisco/enic/enic.h
+++ b/drivers/net/ethernet/cisco/enic/enic.h
@@ -242,6 +242,18 @@ static inline unsigned int enic_msix_notify_intr(struct enic *enic)
        return enic->rq_count + enic->wq_count + 1;
 }
 
+static inline int enic_dma_map_check(struct enic *enic, dma_addr_t dma_addr)
+{
+       if (unlikely(pci_dma_mapping_error(enic->pdev, dma_addr))) {
+               net_warn_ratelimited("%s: PCI dma mapping failed!\n",
+                                    enic->netdev->name);
+
+               return -ENOMEM;
+       }
+
+       return 0;
+}
+
 void enic_reset_addr_lists(struct enic *enic);
 int enic_sriov_enabled(struct enic *enic);
 int enic_is_valid_vf(struct enic *enic, int vf);

diff --git a/drivers/net/ethernet/cisco/enic/enic_main.c b/drivers/net/ethernet/cisco/enic/enic_main.c
index 705f334..142c9b5 100644 (file)
--- a/drivers/net/ethernet/cisco/enic/enic_main.c
+++ b/drivers/net/ethernet/cisco/enic/enic_main.c
@@ -351,80 +351,94 @@ static irqreturn_t enic_isr_msix_notify(int irq, void *data)
        return IRQ_HANDLED;
 }
 
-static inline void enic_queue_wq_skb_cont(struct enic *enic,
-       struct vnic_wq *wq, struct sk_buff *skb,
-       unsigned int len_left, int loopback)
+static int enic_queue_wq_skb_cont(struct enic *enic, struct vnic_wq *wq,
+                                 struct sk_buff *skb, unsigned int len_left,
+                                 int loopback)
 {
        const skb_frag_t *frag;
+       dma_addr_t dma_addr;
 
        /* Queue additional data fragments */
        for (frag = skb_shinfo(skb)->frags; len_left; frag++) {
                len_left -= skb_frag_size(frag);
-               enic_queue_wq_desc_cont(wq, skb,
-                       skb_frag_dma_map(&enic->pdev->dev,
-                                        frag, 0, skb_frag_size(frag),
-                                        DMA_TO_DEVICE),
-                       skb_frag_size(frag),
-                       (len_left == 0),        /* EOP? */
-                       loopback);
+               dma_addr = skb_frag_dma_map(&enic->pdev->dev, frag, 0,
+                                           skb_frag_size(frag),
+                                           DMA_TO_DEVICE);
+               if (unlikely(enic_dma_map_check(enic, dma_addr)))
+                       return -ENOMEM;
+               enic_queue_wq_desc_cont(wq, skb, dma_addr, skb_frag_size(frag),
+                                       (len_left == 0),        /* EOP? */
+                                       loopback);
        }
+
+       return 0;
 }
 
-static inline void enic_queue_wq_skb_vlan(struct enic *enic,
-       struct vnic_wq *wq, struct sk_buff *skb,
-       int vlan_tag_insert, unsigned int vlan_tag, int loopback)
+static int enic_queue_wq_skb_vlan(struct enic *enic, struct vnic_wq *wq,
+                                 struct sk_buff *skb, int vlan_tag_insert,
+                                 unsigned int vlan_tag, int loopback)
 {
        unsigned int head_len = skb_headlen(skb);
        unsigned int len_left = skb->len - head_len;
        int eop = (len_left == 0);
+       dma_addr_t dma_addr;
+       int err = 0;
+
+       dma_addr = pci_map_single(enic->pdev, skb->data, head_len,
+                                 PCI_DMA_TODEVICE);
+       if (unlikely(enic_dma_map_check(enic, dma_addr)))
+               return -ENOMEM;
 
        /* Queue the main skb fragment. The fragments are no larger
         * than max MTU(9000)+ETH_HDR_LEN(14) bytes, which is less
         * than WQ_ENET_MAX_DESC_LEN length. So only one descriptor
         * per fragment is queued.
         */
-       enic_queue_wq_desc(wq, skb,
-               pci_map_single(enic->pdev, skb->data,
-                       head_len, PCI_DMA_TODEVICE),
-               head_len,
-               vlan_tag_insert, vlan_tag,
-               eop, loopback);
+       enic_queue_wq_desc(wq, skb, dma_addr, head_len, vlan_tag_insert,
+                          vlan_tag, eop, loopback);
 
        if (!eop)
-               enic_queue_wq_skb_cont(enic, wq, skb, len_left, loopback);
+               err = enic_queue_wq_skb_cont(enic, wq, skb, len_left, loopback);
+
+       return err;
 }
 
-static inline void enic_queue_wq_skb_csum_l4(struct enic *enic,
-       struct vnic_wq *wq, struct sk_buff *skb,
-       int vlan_tag_insert, unsigned int vlan_tag, int loopback)
+static int enic_queue_wq_skb_csum_l4(struct enic *enic, struct vnic_wq *wq,
+                                    struct sk_buff *skb, int vlan_tag_insert,
+                                    unsigned int vlan_tag, int loopback)
 {
        unsigned int head_len = skb_headlen(skb);
        unsigned int len_left = skb->len - head_len;
        unsigned int hdr_len = skb_checksum_start_offset(skb);
        unsigned int csum_offset = hdr_len + skb->csum_offset;
        int eop = (len_left == 0);
+       dma_addr_t dma_addr;
+       int err = 0;
+
+       dma_addr = pci_map_single(enic->pdev, skb->data, head_len,
+                                 PCI_DMA_TODEVICE);
+       if (unlikely(enic_dma_map_check(enic, dma_addr)))
+               return -ENOMEM;
 
        /* Queue the main skb fragment. The fragments are no larger
         * than max MTU(9000)+ETH_HDR_LEN(14) bytes, which is less
         * than WQ_ENET_MAX_DESC_LEN length. So only one descriptor
         * per fragment is queued.
         */
-       enic_queue_wq_desc_csum_l4(wq, skb,
-               pci_map_single(enic->pdev, skb->data,
-                       head_len, PCI_DMA_TODEVICE),
-               head_len,
-               csum_offset,
-               hdr_len,
-               vlan_tag_insert, vlan_tag,
-               eop, loopback);
+       enic_queue_wq_desc_csum_l4(wq, skb, dma_addr, head_len, csum_offset,
+                                  hdr_len, vlan_tag_insert, vlan_tag, eop,
+                                  loopback);
 
        if (!eop)
-               enic_queue_wq_skb_cont(enic, wq, skb, len_left, loopback);
+               err = enic_queue_wq_skb_cont(enic, wq, skb, len_left, loopback);
+
+       return err;
 }
 
-static inline void enic_queue_wq_skb_tso(struct enic *enic,
-       struct vnic_wq *wq, struct sk_buff *skb, unsigned int mss,
-       int vlan_tag_insert, unsigned int vlan_tag, int loopback)
+static int enic_queue_wq_skb_tso(struct enic *enic, struct vnic_wq *wq,
+                                struct sk_buff *skb, unsigned int mss,
+                                int vlan_tag_insert, unsigned int vlan_tag,
+                                int loopback)
 {
        unsigned int frag_len_left = skb_headlen(skb);
        unsigned int len_left = skb->len - frag_len_left;
@@ -454,20 +468,19 @@ static inline void enic_queue_wq_skb_tso(struct enic *enic,
         */
        while (frag_len_left) {
                len = min(frag_len_left, (unsigned int)WQ_ENET_MAX_DESC_LEN);
-               dma_addr = pci_map_single(enic->pdev, skb->data + offset,
-                               len, PCI_DMA_TODEVICE);
-               enic_queue_wq_desc_tso(wq, skb,
-                       dma_addr,
-                       len,
-                       mss, hdr_len,
-                       vlan_tag_insert, vlan_tag,
-                       eop && (len == frag_len_left), loopback);
+               dma_addr = pci_map_single(enic->pdev, skb->data + offset, len,
+                                         PCI_DMA_TODEVICE);
+               if (unlikely(enic_dma_map_check(enic, dma_addr)))
+                       return -ENOMEM;
+               enic_queue_wq_desc_tso(wq, skb, dma_addr, len, mss, hdr_len,
+                                      vlan_tag_insert, vlan_tag,
+                                      eop && (len == frag_len_left), loopback);
                frag_len_left -= len;
                offset += len;
        }
 
        if (eop)
-               return;
+               return 0;
 
        /* Queue WQ_ENET_MAX_DESC_LEN length descriptors
         * for additional data fragments
@@ -483,16 +496,18 @@ static inline void enic_queue_wq_skb_tso(struct enic *enic,
                        dma_addr = skb_frag_dma_map(&enic->pdev->dev, frag,
                                                    offset, len,
                                                    DMA_TO_DEVICE);
-                       enic_queue_wq_desc_cont(wq, skb,
-                               dma_addr,
-                               len,
-                               (len_left == 0) &&
-                               (len == frag_len_left),         /* EOP? */
-                               loopback);
+                       if (unlikely(enic_dma_map_check(enic, dma_addr)))
+                               return -ENOMEM;
+                       enic_queue_wq_desc_cont(wq, skb, dma_addr, len,
+                                               (len_left == 0) &&
+                                                (len == frag_len_left),/*EOP*/
+                                               loopback);
                        frag_len_left -= len;
                        offset += len;
                }
        }
+
+       return 0;
 }
 
 static inline void enic_queue_wq_skb(struct enic *enic,
@@ -502,6 +517,7 @@ static inline void enic_queue_wq_skb(struct enic *enic,
        unsigned int vlan_tag = 0;
        int vlan_tag_insert = 0;
        int loopback = 0;
+       int err;
 
        if (vlan_tx_tag_present(skb)) {
                /* VLAN tag from trunking driver */
@@ -513,14 +529,30 @@ static inline void enic_queue_wq_skb(struct enic *enic,
        }
 
        if (mss)
-               enic_queue_wq_skb_tso(enic, wq, skb, mss,
-                       vlan_tag_insert, vlan_tag, loopback);
+               err = enic_queue_wq_skb_tso(enic, wq, skb, mss,
+                                           vlan_tag_insert, vlan_tag,
+                                           loopback);
        else if (skb->ip_summed == CHECKSUM_PARTIAL)
-               enic_queue_wq_skb_csum_l4(enic, wq, skb,
-                       vlan_tag_insert, vlan_tag, loopback);
+               err = enic_queue_wq_skb_csum_l4(enic, wq, skb, vlan_tag_insert,
+                                               vlan_tag, loopback);
        else
-               enic_queue_wq_skb_vlan(enic, wq, skb,
-                       vlan_tag_insert, vlan_tag, loopback);
+               err = enic_queue_wq_skb_vlan(enic, wq, skb, vlan_tag_insert,
+                                            vlan_tag, loopback);
+       if (unlikely(err)) {
+               struct vnic_wq_buf *buf;
+
+               buf = wq->to_use->prev;
+               /* while not EOP of previous pkt && queue not empty.
+                * For all non EOP bufs, os_buf is NULL.
+                */
+               while (!buf->os_buf && (buf->next != wq->to_clean)) {
+                       enic_free_wq_buf(wq, buf);
+                       wq->ring.desc_avail++;
+                       buf = buf->prev;
+               }
+               wq->to_use = buf->next;
+               dev_kfree_skb(skb);
+       }
 }
 
 /* netif_tx_lock held, process context with BHs disabled, or BH */
@@ -950,8 +982,12 @@ static int enic_rq_alloc_buf(struct vnic_rq *rq)
        if (!skb)
                return -ENOMEM;
 
-       dma_addr = pci_map_single(enic->pdev, skb->data,
-               len, PCI_DMA_FROMDEVICE);
+       dma_addr = pci_map_single(enic->pdev, skb->data, len,
+                                 PCI_DMA_FROMDEVICE);
+       if (unlikely(enic_dma_map_check(enic, dma_addr))) {
+               dev_kfree_skb(skb);
+               return -ENOMEM;
+       }
 
        enic_queue_rq_desc(rq, skb, os_buf_index,
                dma_addr, len);